Hadron spectroscopy

It has recently been realised that particles such as the neutron or proton, are not in fact elementary, several hundred examples of a probably infinite number of variant types of such particles now being known. It is the set of strongly interacting particles, collectively known as hadrons, which is responsible for the particle population explosion. All except the proton are unstable. The subject of hadron spectroscopy is considered under the following headings; theoretical background (the subatomic particles, baryonic charge and strangeness, isotopic spin, antiparticles and C-parity, SU(3), SU(3) and quarks, SU(6) and the naive quark model), and experimental methods (simple scattering, partial wave analysis, practical scattering experiments, production experiments, SU(3) inelastic scattering). (U.K.)